Method for dividing a subcarrier permutation zone and an information configuration system

ABSTRACT

A method for dividing a subcarrier permutation zone in an Orthogonal Frequency Division Multiple Access system and an information configuration system for dividing a subcarrier permutation zone in the Orthogonal Frequency Division Multiple Access system are disclosed in the present invention. Wherein, the method for dividing the subcarrier permutation zone includes the following steps: a configuration unit performing configuration to a subcarrier permutation zone division information, and sending the subcarrier permutation zone division information to a configuration synchronization unit; the configuration synchronization unit calculating a configuration effective frame number, and sending the subcarrier permutation zone division information and the configuration effective frame number to a base station; the base station dividing the subcarrier permutation zone according to the subcarrier permutation zone division information and the configuration effective frame number. With the present invention, it can uniformly configure, in the whole network, the frame in which the subcarrier permutation zone appears and the position in the frame, so as to avoid the co-frequency interference between each of the adjacent zones.

CROSS REFERENCE TO RELATED APPLICATIONS

This is the U.S. national stage application of PCT/CN20070/003320, filedNov. 7, 2007, the above application is herein incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to communication field, and particularly,relates to a method for dividing a subcarrier permutation zone in anOrthogonal Frequency Division Multiple Access system and an informationconfiguration system for dividing the subcarrier permutation zone in theOrthogonal Frequency Division Multiple Access system.

BACKGROUND OF THE INVENTION

In recent years, Orthogonal Frequency Division Multiplexing (“OFDM” forshort) technology has become a mainstream technology of physical layertechnology in wireless communication because it is capable ofeffectively resisting multipath interference and narrowband interferenceand has a high spectral efficiency. Compared with Code Division MultipleAccess (“CDMA” for short) technology of the 3rd generation, thetechnology of Orthogonal Frequency Division Multiple Access (“OFDMA” forshort) plus Multiple Input Multiple Output (“MIMO” for short) hastechnical advantages of its nature, and is more suitable for broadbandmobile communication system and is generally accepted as one of the coretechnologies of the next generation mobile communication system. IEEE802.16e standard, which uses OFDMA technology as the core technology ofphysical layer and meanwhile takes account of mobility and widebandcharacteristics, is a powerful competitor of the next generation mobilecommunication standard.

In order to support co-frequency networking, the 802.16 standard dividesone carrier frequency into a plurality of segments, each segmentincludes a subcarrier set, in which the subcarriers do not overlap witheach other, in the carrier frequency. Due to the orthogonality of theOFDM subcarriers, there is no co-frequency interference between adjacentcells using different segments of the same carrier frequency. Theprecondition of such performance is that the division rule for thesubcarriers of each segment must be consistent, i.e., the permutationmodes of the subcarriers must be consistent. In general, only when eachsegment uses, by default, a subcarrier permutation zone of the PartialUsage of Sub-Channels (“PUSC” for short), the above condition can beeasily satisfied.

However, in order to support various optional enhancing technologies inthe OFDMA physical layer, the 802.16 standard establishes a plurality ofpermutation methods, including PUSC, Full Usage of Sub-Channels (“FUSC”for short), Full Sub-Channel PUSC, optional FUSC, Adjacent SubcarrierAllocation (“Band AMC” for short), Tile Usage of Sub-Channels-1 (“TUSC1”for short), and Tile Usage of Sub-Channels-2 (“TUSC2” for short). Asshown in FIG. 1, these permutation methods can simultaneously appear inone frame and be divided by permutation zones.

As shown in Table 1 and Table 2, respectively, according to thedescription of 802.16 protocol, in a downlink subframe, the conversionbetween downlink zones is indicated by a Space Time Coding Downlink ZoneInformation Element (“STC_DL_ZONE_IE” for short) or an Adaptive AntennaSystem Downlink Information Element (“AAS_DL_IE” for short) in aDownlink Map (“DL_Map” for short). The OFDMA symbol offset in the abovemessage is an 8-bit field that is used to denote the start position ofthe zone. It can be seen which zones are in each frame and the OFDMAsymbol offset of each zone can be dynamically adjusted in each frameaccording to a certain strategy.

TABLE 1 STC_DL_ZONE_IE Format Fragment Size Syntax (bit) AnnotationSTC_DL_ZONE_IE( ){ — — Extended DIUC 4 STC/DL_ZONE_SWITCH = 0x01 Length4 Length = 0x04 OFDMA symbol offset 8 Denotes the start of thezone(counting from the frame preamble and starting from 0) Permutation 20b00 = PUSC permutation 0b01 = FUSC permutation 0b10 = Optional FUSCpermutation 0b11 = Optional adjacent subcarrier permutation . . . }

TABLE 2 AAS_DL_IE Format Fragment Size Syntax (bit) AnnotationAAS_DL_IE( ){ — — Extended 4 AAS = 0x02 DIUC Length 4 Length = 0x03OFDMA symbol 8 Denotes the start of the zone(counting offset from theframe preamble and starting from 0) Permutation 2 0b00 = PUSCpermutation 0b01 = FUSC permutation 0b10 = Optional FUSC permutation0b11 = Optional adjacent subcarrier permutation . . . }

If adjacent segments use different permutation modes at the same time,since different permutations correspond to different subcarrierpermutation modes, it will inevitably result in that a part of thesubcarriers in the used subcarrier sets conflict with each other, whichleads to interference between signals on the subcarriers, i.e., theco-frequency interference in a macro sense. Next, the PUSC and BandAdjacent Subcarrier Permutation (“Band AMC” for short) will be taken asexamples to explain the situation of mutual conflict between subcarriersof different permutations.

For the PUSC, firstly, a sub-channel is divided into several clusters;each cluster includes 14 consecutive physical subcarriers. Physicalclusters are renumbered according to a renumbering sequence so as toform logical clusters. Then, the logical clusters are allocated intosub-channel groups (for 1024 fast Fourier transform (“FFT” for short),the downlink includes 6 sub-channel groups). Data subcarrier mapping isperformed according to formula (1):subcarrier(k,s)=N _(subchannels) ·n _(k) +{p _(s) [n _(k) mod N_(subchannels) ]+DL_PermBase} mod N _(subchannels)  (1)

Wherein, N_(subchannels) represents the number of the sub-channels; srepresents the serial number of the sub-channel from 0 toN_(subchannels)−1; k represents the subcarrier serial number in thesub-channels; n_(k) represents (k+13·s)mod N_(subcarriers);subcarrier(k,s) represents the sequence number of the physicalsubcarrier corresponding to the k-th subcarrier in the sub-channel s;P_(s)[j] represents the sequence obtained by rotating the permutationsequence to the left for s times; DL_PermBase is a number from 0 to 31,which equals to the cell identifier (ID_Cell) corresponding to atraining sequence (preamble) for the first zone, and is assigned in theIE of the DL_MAP for other zones.

In addition, as shown in FIG. 2, the positions of pilots are denotedaccording to the positions defined in the cluster. From FIG. 2 it can beseen that the positions of the pilots are different when the cluster isof different odd/even symbols.

Wherein, the mapping relation of the cluster is:

${LogicalCluster} = \left\{ {\begin{matrix}{{RenumberingSequence}({PhysicalCluster})} & {{{First}\mspace{14mu}{DL}\mspace{14mu}{zone}\mspace{14mu}{or}}\mspace{14mu}} \\\; & {{{Use}\mspace{14mu}{All}\mspace{14mu}{SC}\mspace{14mu}{indicator}} = 0} \\\; & {{in}\mspace{14mu}{STC\_ DL}{\_ Zone}{\_ IE}} \\{{RenumberingSequence}\left( \left( {{PhysicalCluster} +} \right. \right.} & {Otherwise} \\{\left. {13*{DL\_ PermBase}} \right){mod}\; N_{clusters}} & \;\end{matrix}.} \right.$The 802.16e protocol-8.4.6.1.2.1.1 could be referred to for the detailedprocess.

For Band Adjacent Subcarrier Permutation (Band AMC), with the mode ofadjacent subcarrier permutation, data subcarriers and pilot subcarriersare allocated on consecutive physical subcarriers. Such a permutationmode is the same to the uplink/downlink. In adjacent subcarrierpermutation, the smallest unit is Bin, one Bin being constructed by 9physically consecutive subcarriers. For 1024FFT, one symbol includes 96Bins consecutively arranged according to the sequence of from lowphysical subcarriers to high physical subcarriers, i.e., from 0 to 95.

It can be seen from the above description that the Band AMC isconsecutively arranged according to the subcarriers, while the PUSC isdiscretely arranged according to the subcarriers. Then, in the timeduration of one symbol, there is a situation that the logical data/pilotsubcarriers of two modes correspond to the same physical subcarrier(i.e. subcarrier conflict).

As shown in FIG. 3, in the case of 1024FFT, the mode of 3 segments TimeDivision Duplex (“TDD” for short) 2:1 (the ratio of the length of thedownlink subframe to the length of the uplink subframe is 2:1) isconsidered for networking. In different segments, when the zonepermutation modes in the same symbol duration are different,“overlapping” area will appear between the segments.

In FIG. 3, in the overlapping area between the PUSC MIMO Zone insegment0 and the Band AMC Zone in segment1, the situation of data beingmapped on the same physical subcarrier may appear.

Suppose that the mode for dividing the 3 segments is:

Segment0 occupies subchannel groups (0, 1) and is constructed by themode of PUSC+PUSC MIMO+Band AMC. The symbol offset of the PUSC Zone isfrom 1 to 4; the symbol offset of the PUSC MIMO Zone is from 5 to 14;and the symbol offset of the Band AMC Zone is from 15 to 30. The BandAMC Zone uses logical Band0 to logical Band3.

Segment1 occupies sub-channel groups (2, 3) and is constructed by themode of PUSC+PUSC MIMO+Band AMC. The symbol offset of the PUSC Zone isfrom 1 to 4; the symbol offset of the PUSC MIMO Zone is from 5 to 8; andthe symbol offset of the Band AMC Zone is from 9 to 30. The Band AMCZone uses logical Band4 to Band7.

From symbol offset 9 (symbol 10) to symbol offset 14 (symbol 15) in theSegment0 and the Segment1 is the overlapping area between the PUSC MIMOZone and the Band AMC Zone. Upon calculation, there is the situation ofseveral physical subcarriers overlapping in the overlapping area. Thespecific number of overlapped subcarriers varies according to parameterssuch as subcarrier permutation base (Permbase), segment identification(SegmentID). In the condition of PermBase=0, SegmentID=0, the number ofthe overlapped physical subcarriers is more than 90. When the 3 segmentsare simultaneously considered, the number of the conflicted physicalsubcarriers is even greater.

To sum up, in the application scenario of a plurality of zones in OFDMA,if each segment independently dispatches the position and the size ofeach zone, severe co-frequency interference will occur between adjacentzones.

SUMMARY OF THE INVENTION

In view of one or more problems mentioned above, the present inventionprovides a method for dividing a subcarrier permutation zone in anOrthogonal Frequency Division Multiple Access system and an informationconfiguration system for dividing a subcarrier permutation zone in theOrthogonal Frequency Division Multiple Access system.

The method for dividing the subcarrier permutation zone s in anOrthogonal Frequency Division Multiple Access system according to anembodiment of the present invention comprises the following steps: aconfiguration unit performing configuration to a subcarrier permutationzone division information, and sending the subcarrier permutation zonedivision information to a configuration synchronization unit; theconfiguration synchronization unit calculating a configuration effectiveframe number, and sending the subcarrier permutation zone divisioninformation and the configuration effective frame number to a basestation; the base station dividing the subcarrier permutation zoneaccording to the subcarrier permutation zone division information andthe configuration effective frame number.

Wherein, the configuration unit represents the subcarrier permutationzone division information by means of a division form of the subcarrierpermutation zone. Specifically, the division form of the subcarrierpermutation zone includes one or more kinds of the followinginformation: zone type information, a zone distribution period, anoffset in the zone distribution period, and a zone start symbol offset.

Wherein, the method of the configuration synchronization unitcalculating the configuration effective frame number is adding a currentframe number to a maximum delay of sending the subcarrier permutationzone division information to each of the base stations. Specifically,the configuration synchronization unit determines the maximum delayaccording to the number of the base stations and the specificimplementation of the Orthogonal Frequency Division Multiple Accesssystem.

Wherein, the method for dividing the subcarrier permutation zoneaccording to an embodiment of the present invention further comprisesthe following step: the base station performing dynamic dispatching toeach of the subcarrier permutation zones with the same subcarrierpermutation mode.

Wherein, the method for dividing the subcarrier permutation zoneaccording to an embodiment of the present invention further comprisesthe following step: when a user requests to access into the subcarrierpermutation zone, the base station judging whether to allow the user toaccess into the subcarrier permutation zone according to a Carrier toInterference ratio of the user. Wherein, the process of the base stationjudging whether to allow the user to access comprises the followingsteps: the base station calculating the bandwidth of the media accesscontrol layer allocated to the user according to Carrier to Interferenceratio of the user and the residual slots in the subcarrier permutationzone; if the calculated bandwidth of the media access control layersatisfies the quality of service of the user, allowing the user toaccess the subcarrier permutation zone, otherwise, refusing the user toaccess the subcarrier permutation zone. Wherein, the residual slots inthe subcarrier permutation zone are the residual slots after the qualityof service of existing users in the subcarrier permutation zone issatisfied.

Wherein, the method for dividing the subcarrier permutation zoneaccording to an embodiment of the present invention comprises thefollowing steps: the base station judging, according to the quality ofservice and the channel condition of an accessed user, and the residualslots in target subcarrier permutation zone, whether to allow theaccessed user to switch into the target subcarrier permutation zone; andif the residual slots in the target subcarrier permutation zone satisfythe quality of service of the accessed user, and the channel conditionof the accessed user allows the accessed user to switch, the basestation then performing switching for the accessed user. Wherein, theresidual slots in the target subcarrier permutation zone are theresidual slots after the quality of service of existing users in thetarget subcarrier permutation zone is satisfied.

The information configuration system for dividing a subcarrierpermutation zone in an Orthogonal Frequency Division Multiple Accesssystem according to an embodiment of the present invention comprises: aconfiguration unit, configured to perform configuration to a subcarrierpermutation zone division information, and to send the subcarrierpermutation zone division information to a configuration synchronizationunit; the configuration synchronization unit, configured to calculate aconfiguration effective frame number, and to send the subcarrierpermutation zone division information and the configuration effectiveframe number to a base station.

Wherein, the configuration unit represents the subcarrier permutationzone division information by means of the division form of thesubcarrier permutation zone. The division form of the subcarrierpermutation zone of subcarriers includes one or more kinds of thefollowing information: zone type information, a zone distributionperiod, an offset in the zone distribution period and a zone startsymbol offset.

Wherein, the method of the configuration synchronization unitcalculating the configuration effective frame number is adding a currentframe number to the maximum delay of sending the subcarrier permutationzone division information to each of the base stations. Specifically,the configuration synchronization unit determines the maximum delayaccording to the number of the base stations and the specificimplementation of the Orthogonal Frequency Division Multiple Accesssystem.

With the present invention, it can uniformly configure, in the wholenetwork, the frame in which the subcarrier permutation zone appears andthe position in the frame, so as to avoid the co-frequency interferencebetween each of the adjacent zones.

BRIEF DESCRIPTION OF THE DRAWINGS

The figures illustrated here provide a further understanding of thepresent invention and form a part of the application. The exemplaryembodiments of the present invention and description thereof are used toexplain the present invention without unduly limiting the scope of theinvention. Wherein:

FIG. 1 is a logical structure diagram of an OFDMA frame according to anembodiment of the present invention;

FIG. 2 is a diagram of a cluster structure according to an embodiment ofthe present invention;

FIG. 3 is a diagram of interference between a plurality of zones indifferent segments according to an embodiment of the present invention;

FIG. 4 is a structure diagram in a wireless communication system of aplurality of zones in OFDMA according to an embodiment of the presentinvention;

FIG. 5A to FIG. 5D are the exemplary figures of a dynamic zone divisionaccording to an embodiment of the present invention; and

FIG. 6 is an exemplary figure of a dynamic zone division according toanother embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

The present invention aims at solving the problem of the co-frequencyinterference in the application scenario of a plurality of zones in theOFDMA. The present invention provides a method and a system ofconfiguring, uniformly in the whole network, the frame in which thepermutation zone appears and the position in the frame (i.e. the methodfor dividing a subcarrier permutation zone and an informationconfiguration system for dividing the subcarrier permutation zoneaccording to the embodiments of the present invention), which canensure, in the whole network, the subcarrier permutation modes in allsegments are identical at the same time. Besides, the present inventionalso provides a method for improving the resource utilization rate in afixed zone.

As shown in FIG. 4, the system of uniformly configuring, in the wholenetwork, the frame in which the permutation zone appears and theposition in the frame, according to an embodiment of the presentinvention, comprises an operation and maintenance console (“OMC” forshort) and base stations, wherein, the OMC is connected to each of thebase stations in the whole network, and comprises a configuration unitand a configuration synchronization unit.

Wherein, the method for dividing the permutation zone using the systemshown in FIG. 4 comprises the following steps:

A. A Zone Division Form is configured by the configuration unit on theOMC, wherein, the Zone Division Form is in the following format:

TABLE 3 Zone Division Form Format Zone Type Frame Intval Frame OffsetSymbol Offset

The Zone Type represents a zone type index, each zone type correspond toa group of zone characteristic parameters, and the subcarrierpermutation modes in the zones identified by different zone types aredifferent (such as different Permutation, Permbase and etc.).

The Frame Intval, in the unit of frame, represents the period allocatedfor the zone, i.e., the zone is allocated in the frame of each FrameIntval.

The Frame Offset represents the offset of the zone in the period of theFrame Intval. The Frame Offset can be a sequence, for example, the FrameOffset={0, 1, 3}. When the Frame Intval=4, and the frame number % theFrame Intval=0, 1, or 3, the zone must be allocated.

The Symbol Offset represents the start symbol offset of the zone in theframe, when Symbol Offset=0, it represents a Preamble. The end symbol ofthe zone is equal to the start symbol of the next zone−1, and if thenext zone does not exist, the end symbol of the zone is equal to thelast symbol of the subframe.

Each frame must have the Mandatory PUSC Zone including the FCH and theDL Map according to the 802.16 protocol, and the Symbol Offset=1, thedefault zone may not be recorded in the above form (or the zone is shownbut does not allow to be changed, and represented as PUSC0 in thesubsequent description).

B. The configuration unit sends the configuration data to aconfiguration synchronization unit. The configuration synchronizationunit calculates a configuration effective frame number by a method ofadding a current frame number to the maximum delay after synchronizingeach of the base stations. The delay can be a fixed empirical value, oris related to the number of the base stations that need to besynchronized, and is related to a specific system implementation.

C. The configuration synchronization unit sends the configuration datato each of the base stations, including the Zone Division Form in Step Aand the configuration effective frame number in Step B.

D. After receiving the configuration data, each base station, accordingto the configuration effective frame number, distributes the zoneaccording to new Zone Division Form starting from the configurationeffective frame number.

The method can implement the support for any zone, through configuringparameters, which is able to fully utilize the bandwidth of the airinterface, and uniformly configure zones in the whole network, andmeanwhile keep the number of zones simultaneously distributed in oneframe meeting the requirement of the protocol (in the 16e protocol, thenumber of zones simultaneously included in a downlink subframe islimited). In such a scheme, the zones can be divided according to theactual requirement of business volume, i.e., in one frame, theconstruction of the Zone Type can be configured, so that the bandwidthutilization rate is relatively high. Absolute frame numbers in the wholenetwork are consistent, and all base transceivers (BTS) are uniformlyswitched so as to realize a co-channel multi-zone networking in thecondition of utilizing the bandwidth as much as possible.

The simplest application of the method is dividing the zones in a samesubframe. That is, in each subframe, the zone area and the zone positionare designated for each kind of the zones, as shown in FIG. 6. Thenumber (n), position (Pos) and size (length in symbol) of the zone canbe decided according to the actual requirement. After the zone division,the co-frequency interference will not exist anywhere in the wholenetwork.

Implementing a co-frequency networking using the mode of fixed zonedivision requires the support of a corresponding dispatching mechanism;otherwise, the utilization rate of wireless resources will be inevitablydecreased. Since the zone division is fixed, if the data quantity in acertain zone is relatively small, the resources in this zone will bewasted. In order to solve such a problem, the following method isprovided according to an embodiment of the present invention:

1) Performing dynamic dispatching between the zones of the samesubcarrier permutation. The zones of the same subcarrier permutation(for example, of the same Permutation and PermBase) are put togetherupon considering the data allocation. However, the boundary of theZone-Allocation also needs to be ensured. The utilization of thebandwidth in the zones of the same subcarrier permutation can be ensuredto the largest extent by dividing the sizes (positions) of differentzones according to the actual quantity requirement of the user. Forexample, in the PUSC and the PUSC-MIMO, the carrier permutation modes ofthe two kinds of zones can be the same, but they also need to be dividedinto 2 zones. In this case, the total resources of the two parts can beconsidered together so that the actual requirement of the user of thePUSC and the PUSC-MIMO can be well considered, and meanwhile, nointerference to the data in other segments is caused.

2) Upon accessing, whether to allow a user to be admitted into thesystem is judged in the system admission control. The specific methodis: the admission control, according to a current Carrier toInterference and Noise ratio (“CINR” for short) of the user (or thesupported highest order Modulation and Coding (“MCS” for short), the MCSof terminal can be obtained before the admission flow comes to theadmission control) and the number of residual slots after the quality ofservice (QoS) of existing users in the PUSC-Zone is satisfied,calculates the bandwidth of the media access control (MAC) layer thatcan be allocated to the terminal. If the bandwidth could meet the QoSrequirement of the terminal, then, the user will be admitted into thesystem; otherwise, the access requirement of the user will be refused.When the PUSC zone cannot admit any new user, it will refuse to admit auser that does not support the PUSC-MIMO. If it is found that thePUSC-MIMO zone also cannot admit any new user, a user that supports theMIMO will be refused. After the user accesses the system, the users willbe allocated among the zones to implement load sharing and improve theresource utilization rate.

3) The different zones and the QoS of the terminal are considered forload balancing. After the flow of terminal basic capability negotiation(SBC), though the terminal exchanges supported zone types with the basestations, it does not mean that the terminal can surely run servicesaccording to the permutation mode of the zone. For example, one usersupports the Band-AMC, but after the terminal accesses the system, aperiod of time is needed for judging the channel condition to seewhether the terminal can run the services according to the mode of theBand-AMC. If all the accessed terminals concentrate in the PUSC-Zone,the bandwidth of the PUSC-Zone will be used up very soon, and thebandwidth of the Band-AMC zone will be wasted. Thus, after the useraccesses the system, zone still needs to be switched. The specificmethod is: the system judges whether to allow the user to be switchedinto other zones according to the QoS basic requirement of the accesseduser and the number of the residual slots after the zone meets the QoSrequirement of the existing terminals (meeting the lowest requirement ofthe QoS) and the channel condition of the user (for example, channelstability). If the residual bandwidth of the corresponding target zonestill can meet the QoS of the new users after meeting the QoS of theexisting terminals, and the channel condition allows the user to switchzone, the system initiates the switching of the user between the zones,i.e., the user is switched from current zone to a target zone (forexample, switching from the PUSC to the AMC).

4) Since the structures of the zones in different frames are different,the residual physical bandwidths of different zones after meeting theQoS as mentioned in the above description are statistic values whosecounting period depends on the specific design (or requirement), forexample, they can be counted every 0.2 second, 0.5 second, or 1 second,according to the requirement of the actual operating.

Suppose a downlink multi-zone configuration is as shown in Table 4:

TABLE 4 An Example of the Zone Division Configuration Zone Type FrameIntval Frame Offset Symbol Offset 1(pusc1) 4 0 11 2(pusc2) 4 2 113(fusc) 4 1 13 4(amc) 4 3 15 5(amc) 4 1 15

The PUSC0 is a compulsory zone of the downlink subframe. When theabsolute frame number FrameNo in the whole network is 4*k, 4*k+1, 4*k+2,4*k+3, the structures of the downlink subframes are respectively asshown in FIGS. 5A, 5B, 5C, 5D. In the situation of ensuring theconsistency of the FrameNo in the whole network, the subcarrier mappingrelations corresponding to all base stations (BS) are the same at anytime (symbol). Then, the data in the zones will not be interfered.Meanwhile, the number of zones in one frame meets the protocolrequirement.

Since there are still a plurality of the different zone types in thetime period, then, the resource utilization rate can be improvedaccording to the method of the embodiments of the present invention.

When FrameNo=4*k, the structure of the frame is as shown in FIG. 5A.Presume the PUSC (0) and the PUSC (1) are two zones that have the samesubcarrier permutation. But for different applications (for example, thePUSC and the PUSC-MIMO), presume the total bandwidths of the two zonesare 300 Slots. At this time, there are two users, namely, user 1 anduser 2. User 1 can only be put in zone PUSC (0) and user 2 can only beput in PUSC (1). Consider the following two kinds of situations of thebandwidth requirement of the users: situation 1): the bandwidthrequirement of user 1 is 150 Slots, and that of user 2 is 150 Slots;situation 2): the bandwidth requirement of user 1 is 120 Slots, and thatof user 2 is 180 Slots.

Compare the methods of the zone division. If the two zones are dividedhaving the sizes (position) of 150 slots and 150 slots, respectively,under the requirement of user situation 1), both users can be satisfied,and the bandwidths will not be wasted; and under the requirement of usersituation 2), the requirement of all the 120 slots of the first user canbe satisfied, while only 150 slots of the requirement of 180 slots ofthe second user can be satisfied. Thereby, the 30-slot space in zonePUSC (0) is wasted, and the bandwidth requirement of user 2 is notsatisfied. At this time, the system bandwidth is not fully utilized.

If the dynamic dispatching is used, the zone division will depend uponthe actual requirements of the users in the zones. After the completionof dispatching, in situation 1), after the data of the users is put intothe zones, the PUSC (0) and the PUSC (1) are of the same sizes, i.e. 150slots. In situation 2), the bandwidth of the PUSC (0) is 120 slots, andthe bandwidth of the PUSC (1)-Zone is 180 slots. Comparing the twosituations, the positions of the two zones, i.e., the PUSC (0) and thePUSC (1), are changed, which is the dynamic dispatching. This kind ofdynamic dispatching not only ensures non-interference between user datain the same subcarrier permutation zones, but also improves thebandwidth utilization rate.

Presume the downlink subframe comprises three zones, which are the PUSC,the PUSC-MIMO, and the Band-AMC, respectively. The zone types supportedby a user can be known after the user performs a basic capabilitynegotiation (SBC). The user may only support the PUSC, or also supportthe MIMO, or the Band-AMC. Since the positions of the differentsubcarrier permutation zones need to be designated, it may easily causetoo many users to be allocated into the PUSC-Zone resulting in that thePUSC-Zone is filled up while other zones are vacant. Load sharing isrequired with respect to such a situation. The user must pass theadmission control upon accessing. In the admission control, whether toallow a new user to be admitted is judged according to the residualbandwidth, the MCS of the user and the zone type supported. For example,when user 0 is trying to access the system, it is found, after thecompletion of the SBC, that user 0 supports the PUSC, the PUSC-MIMO andthe Band-AMC. Then, the system judges the residual bandwidths ofdifferent types of zones after satisfying the QoS of the existing users,for instance, the residual bandwidths of PUSC, MIMO and AMC are 20slots, 30 slots, 30 slots, respectively; and then, the current CINR(FEC) of the user is obtained, for example, it is 16Qam½. The MACbandwidth that the residual bandwidth of each zone could provide to theuser is PUSC=20*6*2*8*200=384 kbps, MIMO=30*6*2*8*200=576 kbps,AMC=30*6*2*8*200=576 kbps, respectively. Presume the bandwidthrequirement meeting the QoS of the user is 96 kbps at this time. Sincethe user supports the MIMO and the AMC modes, and the residual bandwidthprovided by any zone can satisfy the QoS bandwidth requirement of theuser, it is chosen to admit the user into the system. Since it is notsure that a user can operate according to a non-PUSC mode afteraccessing the system, it is firstly put into the zone of the PUSC afterbeing admitted. After the admission of the new user, the residualbandwidths of the three zones are 288 kbps, 576 kbps and 576 kbps,respectively. Since the user supports the MIMO, the data of the user canbe put into the MIMO zone very soon. After the user is put into the MIMOzone, the residual bandwidths of the three zones are PUSC=384 kbps(restored), MIMO=480 kbps (96 kbps being removed), AMC=576 kbps,respectively. Subsequently, a new user 1 appears. During this period oftime, the system finds that user 0 can operate according to the AMCmode, user 0 is transferred from the MIMO-Zone into the AMC-Zone. Theresidual bandwidths of the zones are renewed after the transfer:PUSC=384 kbps, MIMO=576 kbps (restored), AMC=480 kbps (96 kbps beingremoved). User 1 supports the PUSC and the MIMO after the SBC, and theQoS requirement is 96 kbps. The system admits the user, and predicts toput it into the MIMO zone, renews the residual bandwidths of the zones:PUSC=288 kbps, MIMO=576 kbps, AMC=480 kbps. Then, a new user 3 appears.After SBC, it is found that the FEC of the PUSC supported by the useralso has 16Qam½, and the QoS requirement is 96 kbps. Since the user doesnot support the MIMO, it can only be put into the PUSC zone. Residualcapacities of the zones are continuously renewed: PUSC=172 kbps, MIMO=76kbps, AMC=480 kbps. Since the user supports the MIMO, if the conditionsare satisfied, user 1 is switched from the PUSC-Zone to the MIMO-Zone.The capacities of the zones are renewed: PUSC=288 kbps (96 kbps beingadded), MIMO=480 kbps, AMC=480 kbps.

Through this method, the spaces of zones differently divided can beeffectively utilized, which greatly improves the resource utilizationrate.

The above description is only to illustrate the preferred embodimentsbut not to limit the present invention. Various alterations and changesto the present invention are apparent to those skilled in the art. Thescope defined in claims shall comprise any modification, equivalentsubstitution and improvement within the spirit and principle of thepresent invention.

What is claimed is:
 1. A method for dividing a subcarrier permutationzone for a first base station and a second base station in an OrthogonalFrequency Division Multiple Access system, comprising the followingsteps: a configuration unit performing configuration to subcarrierpermutation zone division information for the first base station and thesecond base station, and sending the subcarrier permutation zonedivision information to a configuration synchronization unit; theconfiguration synchronization unit calculating a configuration effectiveframe number, wherein the configuration effective frame number isdependent on a maximum time delay required for synchronizing the firstbase station with the second base station, and sending the subcarrierpermutation zone division information and the configuration effectiveframe number to the first base station and the second base station; thefirst base station dividing its frames into a first plurality ofsubcarrier permutation zones according to the subcarrier permutationzone division information and the configuration effective frame number;and the second base station dividing its frames into a second pluralityof subcarrier permutation zones according to the subcarrier permutationzone division information and the configuration effective frame numbersuch that, at any given moment, a first frame associated with the firstbase station and a first frame associated with the second base stationhave an identical permutation mode.
 2. The method for dividing thesubcarrier permutation zone according to claim 1, wherein theconfiguration unit represents the subcarrier permutation zone divisioninformation by means of a division form of the subcarrier permutationzone.
 3. The method for dividing the subcarrier permutation zoneaccording to claim 2, wherein the division form of the subcarrierpermutation zone includes one or more kinds of the followinginformation: zone type information, a zone distribution period, anoffset in the zone distribution period and a zone start symbol offset.4. The method for dividing the subcarrier permutation zone according toclaim 3, wherein the method of the configuration synchronization unitcalculating the configuration effective frame number is adding a currentframe number to the maximum time delay required for synchronizing thefirst base station with the second base station.
 5. The method fordividing the subcarrier permutation zone according to claim 2, whereinthe method of the configuration synchronization unit calculating theconfiguration effective frame number is adding a current frame number tothe maximum time delay required for synchronizing the first base stationwith the second base station.
 6. The method for dividing the subcarrierpermutation zone according to claim 1, wherein the method of theconfiguration synchronization unit calculating the configurationeffective frame number is adding a current frame number to the maximumtime delay required for synchronizing the first base station with thesecond base station.
 7. The method for dividing the subcarrierpermutation zone according to claim 1, wherein the maximum delay isdetermined according to a number of base stations and a specificimplementation of the Orthogonal Frequency Division Multiple Accesssystem.
 8. The method for dividing the subcarrier permutation zoneaccording to claim 7, further comprising the following step: each of thefirst base station and the second base station performing dynamicdispatching to each of the subcarrier permutation zones with the samesubcarrier permutation mode.
 9. The method for dividing the subcarrierpermutation one according to claim 7, further comprising the followingstep: when a user requests to access into a subcarrier permutation zoneassociated with a respective one of the first base station and thesecond base station, the base station judging whether to allow the userto access into the subcarrier permutation zone according to a Carrier toInterference ratio of the user.
 10. The method for dividing thesubcarrier permutation zone according to claim 9, wherein the process ofthe base station judging whether to allow the user to access comprisesthe following steps: the base station calculating the bandwidth of themedia access control layer allocated to the user according to theCarrier to Interference ratio of the user and residual slots in thesubcarrier permutation zone; if the calculated bandwidth of the mediaaccess control layer satisfies the quality of service of the user,allowing the user to access the subcarrier permutation zone; andotherwise, refusing the user to access the subcarrier permutation zone,wherein the residual slots in the subcarrier permutation zone are theresidual slots after the quality of service of existing users in thesubcarrier permutation zone is satisfied.
 11. The method for dividingthe subcarrier permutation zone according to claim 7, further comprisingthe following steps: the base station judging, according to the qualityof service and the channel condition of an accessed user, and theresidual slots in a target subcarrier permutation zone, whether to allowthe accessed user to switch into the target subcarrier permutation zone;and if the residual slots in the target subcarrier permutation zonesatisfy the quality of service of the accessed user, and the channelcondition of the accessed user allows the accessed user to switch, thebase station performing switching, for the accessed user, wherein theresidual slots in the target subcarrier permutation zone are theresidual slots after the quality of service of existing users in thetarget subcarrier permutation zone is satisfied.
 12. An informationconfiguration system for dividing a subcarrier permutation zone for afirst base station and a second base station in an Orthogonal FrequencyDivision Multiple Access system, comprising: a configuration unit,configured to perform configuration to subcarrier permutation zonedivision information for the first base station and the second basestation, and to send the subcarrier permutation zone divisioninformation to a configuration synchronization unit; and theconfiguration synchronization unit, configured to calculate aconfiguration effective frame number, wherein the configurationeffective frame number is dependent on a maximum time delay required forsynchronizing the first base station with the second base station, andto send the subcarrier permutation zone division information and theconfiguration effective frame number to the first base station and thesecond base station; wherein the first base station is configured todivide its frames into a first plurality of subcarrier permutation zonesaccording to the subcarrier permutation zone division information andthe configuration effective number; and the second base station isconfigured to divide its frames into second plurality of subcarrierpermutation zones according to the subcarrier permutation zone divisioninformation and the configuration effective number such that, at anygiven moment, a first frame associated with the first base station and afirst frame associated with the second base station have an identicalpermutation mode.
 13. The information configuration system for dividingthe subcarrier permutation zone according to claim 12, wherein theconfiguration unit represents the subcarrier permutation zone divisioninformation by means of a division form of the subcarrier permutationzone.
 14. The information configuration system for dividing thesubcarrier permutation zone according to claim 13, wherein the divisionform of the subcarrier permutation zone includes one or more kinds ofthe following information: zone type information, a zone distributionperiod, an offset in the zone distribution period and a zone startsymbol offset.
 15. The information configuration system for dividing thesubcarrier permutation zone according to claim 14, wherein the method ofthe configuration synchronization unit calculating the configurationeffective frame number is: adding a current frame number to the maximumtime delay required for synchronizing the first base station with thesecond base station.
 16. The information configuration system fordividing the subcarrier permutation zone according to claim 13, whereinthe method of the configuration synchronization unit calculating theconfiguration effective frame number is: adding a current frame numberto the maximum time delay required for synchronizing the first basestation with the second base station.
 17. The information configurationsystem for dividing the subcarrier permutation zone according to claim12, wherein the method of the configuration synchronization unitcalculating the configuration effective frame number is: adding acurrent frame number to the maximum time delay required forsynchronizing the first base station with the second base station. 18.The information configuration system for dividing the subcarrierpermutation zone according to claim 12, wherein the maximum delay isdetermined according to a number of base stations and a specificimplementation of the Orthogonal Frequency Division Multiple Accesssystem.